Improvement in grate-bars



UNITED STATES PATENT OEEIoE.

GLEMENTS A. GREENLEAF, OF INDIANAPOLIS, INDIANA.

IM PROVEM ENT IN GRATE-BARS.

Specification forming part of Letters Patent No. 96,798, dated November 16, 1869.

I, (ELEMENTS A. GREENLEILF, of Indianapolis, in the county of Marion and State of 1ndiana, have invented an Improved Furnace Grate-Bar, of which the following is a specification:

My invention relates to the combination of curved cross-pieces with and between parallel side plates to form a grate-bar, said side plates being provided with a continuous serie-s of projections, so formed as to leave intermediate recesses along the entire length thereof.

The object of my invention is to produce a grate-bar which may expand laterally with less danger of fracture and less liability to warp or twist than the grate-bars constructed with straight cross-pieces, and which will not clog nor choke, and may be readily freed and cleansed from clinker.

Figure 1 of the accompanying drawing is a plan view of my improved grate-bar; Fig. 2, an end view of the same.

The entire bar is cast in one piece and is solid.

A A are its longitudinal side plates, B B, a series of narrow curved cross-pieces, which leave intervening curved openings, c c, widthwise of the bar.

The longitudinal side plates A, which support the weight of the charge in the furnace, are, as usual, made about one-half wider than the cross-pieces B, as illustrated in Fig. 2 of the drawings.

The lower or under edge of the curved crosspieces B B are cast with a .re-entrant curve, which reduces their width, so that they can be more readily relieved or freed from ashes collecting from any cause between them.

D D are exterior projections, an inch or more in length, extending from the upper edge of the side plates down upon the outer faces thereof transversely to the length of the bar. These are so formed, in the manner shown in Fig. 1 of the drawings, as that the spaces or recesses e e left between them are semi-cylindrical. Hence, when any two or more of the grate-bars are placed side by side, these recesses form a series of cylindrical apertures between the bars, and consequently there are no dead or blank spaces in any part of the grate formed therewith'.

The recesses e e need not necessarily be semi-cylindrical. They may be oblong or an gular, for their form is immaterial.

The arched or curved form` of the crosspieces B B, in combination with the width of the bar, prevents any possibility of a warping or twisting of the bar when exposed to the ordinary heat of a furnace, and its peculiar form enables it to resist the efects even of severe and unequal exposure to heat. The series of projections D D, which afford support to the sides of the bars along their entire length, add to their security in this respect, so that the grate formed therewith will maintain a more even and uniform surface than it is possible to secure with the ordinary gratebars having straight cross-pieces, whether said cross-pieces are arranged at right angles to the side plates or at an inclination thereto.

The curved openings c cfacilitate the scraping and clearing of the upper surface of the bars, as the scraper will draw and grind the clinkers which may project into said openings against the sides thereof, and thus operate to crush them.

I am aware that grates and grate-barshave been constructed and used in which the transverse bars have been arched or curved up-Y wardly in a vertical plane so that the upper surface of the grate or bar is arched.

I do not therefore claim, broadly, curved cross-pieces combined with laterall bars to form a grate-bar.

My invention relates only to the use of cross-pieces curved or bent in a horizontal plane between suitable side bars, so that the entire upper surface of the grate-bar shall be iiat and level 5 and I claim as new therein and desire to secure by Letters Patent- A furnace grate-bar constructed, as herein described, of longitudinal side plates, separated by intermediate cross-pieces, bent or curved in a horizontal plane, with their upper edges flat, substantially as herein` set forth.

The foregoing speciiication of my improved grate-bar for furnaces signed by me this 14th day of September, 1869.

GLEMENTS A. GREENLEAF.

Witnesses:

J. L. MoTHERsHEAD, GEORGE MILLER. 

